Astronauts of the future could receive text, graphics and even video through a wearable computer built into their space suits.

At present, during space walks, astronauts get their instructions via radio.

But the American space agency (Nasa) reckons the way to maximise information exchange is to send it visually into the astronaut's helmet.

WearSAT components

Low power embedded Risc microprocessor

IEEE 802.11B wireless network

VGA head mounted near-eye microdisplay

One gigabyte microdrive storage

Fitting the upgraded communications equipment into the space suit means kitting the astronauts out with a wearable computer.

"The goal of WearSAT is to provide astronauts who are working outside the International Space Station on a space walk with visual information through a display, a wireless video terminal and a wearable computing system," said Steven Schwartz, project manager of the WearSAT project at the Massachusetts Institute of Technology.

"So that they can receive enhanced information while performing the task that they do on such space walks," he told the BBC programme Go Digital.

A wireless network would allow controllers on the space station to beam complex information, such as schematics and technical diagrams, right into the astronaut's helmet.

Computer on the chest

At MIT, Chris Carr is one of the team working on squeezing the wearable technology into the space suit.

Space on the suit is at a premium

"What we're doing essentially is using the small amount of unused space within the suit to build a body conformable computer and provide them with a display system that does not require modifications to the current suit," said Mr Carr.

Modifying the existing suit is out of the question because each one costs between US$10m and US$20m.

So, researchers have identified where best in the space suit to locate the new technology.

"The upper torso of the suit is actually a rigid composite structure and that basically serves as a mounting point for all the other things that have to be attached to the suit, for example, the life support backpack, the display and control module," said Mr Carr.

"Currently that is the only place in the suit where extra components are inserted in the suit."

Head-up display

One of the big challenges was finding a way of fitting a display into an astronaut's helmet.

Near-eye microdisplay delivers text and video

"Using new technology, which is referred to as the microdisplay, we were able to fit a small active matrix liquid crystal display around an area where eye glasses would normally be worn," said Mr Schwartz.

The project by MIT and Boeing aims to demonstrate a practical application of wearable computing.

Researchers hope to have the technology in place over the next three years.